Speedometer



Patented hier. 1925.

eifel TGTH, OF LGS Allf SIJEEBOME'LER.

Application filed April i?, 1922.

To Ao!! IIii/10m t may concern:

lgle it known that l. STEVEN Torn', a citizen oi the United States, residingl at Los Angeles, in `the count)Y oft Los Angeles and State oit' California, have invented new and .iseliul lniprovements in tilpeedometers, oif which the 'following is a specilication.

My `invention relates to speedometers coinmonly used in connection with motor propelled vehicles tor indicating the speed at which the vehicle is running7 and more particularly pertains to means toi-engaging 'the indicating dialfoc the speedometer and holding the same from returning to rero7 in order to indicate the actual speed at which he vehicle was moving when brought to a sudden stop by an application ot the brakes or hij colliding with `some ohjeet.

ll'hen collisions 'occur in the driving olf :,mton'lohiles. disputes often arise between '.he colliding` parties as well ras with the traliic authorities as to the speed the vehicle was i when` the accident transpired. it is the main object Vot 1nj,"invention lo provide a device which will register the `peed at which the vehicle' upon which it is installed was moving when lirongght to sudden stop, and therehjr present` satis'iar "orjff evident-e to the parties concerned as to nvlio was at -it'ault.

notherpohject ot my invention is 'to provide a simple ineelnmisin tor accomplishing the ahove recited 4objects which may he readilyv incorporated with the mechanism ol'v speedometers now in `general use.

.i 'further object is to gn'ovide means Jfor automaticalhv releasing the indicating dial when the vehicle is again started and allowing; the speedometer to again perform its iis-nal tnnction Other objects ot my invention will he more 't'nlljy disclosedin the 'following description and are embodied in the acconipanving drawings, in which:

Fig. l is a plan view. with the cover reniovefl. ot a ma g'neticallyY operated speed orneter ot a well known type. showing' in v invention implied thereto. the mechanism heilig stationary.

l? 2 is a sertional view ol the same n on the line 2-2 ot Fig. l, the mechanism rotating.

Fig. 3 is a ragmental view showing the dial control spring.

in carrying out my invention l have illus- `led :i ma@noticallyY operated speedometer oi? a well linown construction, in which 5 represent4 the casing, (5' the cover thereof, i a hase plate mounted therein provided with the hearing' in, which is journaled the shaft tl provided at its inner end with the rotor l0 upon which the magnet 'il is mounted, and at its opposite end 127 with means wherein' the usual Vtlexihle shatt't not shown) which is adapted to lead to the vehicle wheel and to he driven thereby in the usual manner mayr he att-ached.`

The shait A9 is provided with a Worinl lil adapted to engaoje with a worm Wheel lil mounted on a shatt l5 journaled in hearings 1G `securedy to the hase Vplate 7, and secured to shalt is a worm 1T adapted to engage with a worn wheel i8 secured to a shaft l5) which is provided on its oppositie ond with a worm 2() adapted 'to drive otherV meclninism, which is not shown as it .terms no speci'lic part ot this invention.

Secnredto a shalt 2l is the usual indicating' dial drinn 22 adapted to surround the m'aejnet ll and 'to he controlled hv the mafrnetictorces up thereby. upon varir speeds ot rotation thereoitnl to indicate the speed the vehicle is heilig driven.

The shalt 2l`passes through a centrally disposed hore 2 3 in ther shaft 9 and its end 2l is 'formed into a needle point which is journaled in a slidalile hloclr mounted in saidihore7 a spring 26 being interposed between said block and the end 7all ot" the here. The opposite end ot the shaft 2l passes through and is loosel7 journaled in a here 27 formed in a plate 28 secured to the base plate 7, and the extreme end 24 of said shaft rests against a thrust plate 3() which is also secured to the hase plate 7. The plate 28 is provided with a lug 31 to which one end of a coil spring 32 is secured7 the other end oit said spring being secured to a, huh 33 secured to the shaft 21. The, dial drum 22 is provided with a pin 34 adapted to he normally held against a. stop pin secured to plate 28 by means of the spring 32 When the speedometer :is inoperative to expose the zero numeral through the aperture 36 formed in the cover G,

The dial drum 22 is provided on its peripheral edge with a. plurality of teeth 87 adapted to be engaged, as will hereafter be ei:- plained,by the knife edged blade 38 which is secured to the shaft 9. A spring` 39 surrounds the shatt- 9 and is interposed between a shoulder formed thereon and a shoulder in titl 2 Lacasse the bearing of said shaft, as clearly shown in Fig. 2 of the drawings.

In Fig. l of the drawings the mechanism is shown in a passive state, that is, the speedometer is inoperative, and in Fig. 2 the mechanism is shown in an active state, the speedometer operating to perform its usual function.

The shaft 9 is adapted to have a slight longitudinal movement in the bearing 8, the spring 39 tending to thrust the shaft inwardly in a position indicated in F ig. l to hold the blade or pawl 88 in engagen'ient with the teeth 3T and thereby lock the dial `lrum 22 to the shaft 9, the lost motion between the teeth of the various worms and worm gears permitting of this longitudinal movement of the shaft.

When the sha-ft 9 is started to rotate the hrust caused by the resistance of the gearing and mechanism which is operated thereby is suiiicient to overcome the resistance of the spring 39 and as a consequence the shaft 9 will be thrust outwardly as shown fn Fig. 2, thereby releasing the blade 88v from engagement with the dial drum, thus permitting said drum to perform its func- -tion of registering the speed at which the vehicle is running.

When the vehicle is suddenlystopped the shaft 9 becomes instantly7 inactive, the thrust of the mechanism driven thereby is released therefrom and the spring 39 at once acts to throw the blade 38 into engagement with `he dial drum, thus locking said drum to the inactive shaft before the return spring 32 can act to return it to indicate Zero. By this action it will be evident that the numeral on the dial drum will be displayed to indicate the speed the vehicle was running when brought to a sudden stop and will continue to be exposed until the vehicle is again started.

During the above recited operations it will be evident that the dial 22 will be held from sliding with respect to the shaft 9 by means of the spring pressed bearing block 25.

Although I have illustrated and described only one specific mechanism for accomplishing the desired result, it will be obvious that the broad idea of my invention may be accomplished by other constructions and may be applied to speedometers of other types.

What I claim is:

l. In a speedometer, a rotary speed indieating dial, a rotatable and reciprocatory mounted shaft, means associated with said dial and shaft for rotating said dial to indicate the speed at which said shaft is revolving, and means for locking said dial and shaft together and unlocking them from each other upon a reciprocation of said shaft.

2. In a speedometer, a speed indicating dial, a rotatably mounted shaft adapted to be automatically reciprocated in one direction when not rotating and in an opposite direction when rotating, means associated with said dial and shaft for actuating said dial to indicate the speed at which said shaft is revolving, and a clutch mechanism actie ated by the reciprocating movement of said shaft adapted to engage with said dial when said shaft is not revolving and to become disengaged from said dial when said shaft starts to revolve.

In witness that I claim the foregoing I have hereunto subscribed my name this 28th day of March, 1922.

STEVEN TOTH, 

